Potting Mix


September 01, 2000 / 49(34);777-8 

Legionnaires' Disease Associated With Potting Soil --- California, Oregon, and Washington,

May--June 2000

Since Legionnaires' Disease (LD) was first reported in 1976, outbreaks have been associated with airborne transmission of Legionella bacteria through cooling towers, showers, and other aerosolizing devices (1).
However, most LD cases are sporadic, and the source and mode of infection in many cases are unknown.
Infections with one species, Legionella longbeachae, have been associated with gardening and use of potting soil in Australia and Japan (2,3). This report summarizes the findings of LD investigations in California, Oregon, and Washington, that suggest that transmission from potting soil has occurred for the first time in the United States, and
that active surveillance and case finding are warranted to explore this association. 

On June 13, 2000, CDC was alerted by a county health official in Washington of L. longbeachae infection in a 46-year-old woman who had been hospitalized with pneumonia. The patient reported that she had been potting plants during the 10 days before her symptoms began in May. An isolate from the patient's sputum was sent to CDC for species confirmation, and two samples of potting soil and one of compost from the original packages obtained from the patient's residence were sent for analysis. L. longbeachae was isolated from one potting soil sample. The compost contained other Legionella species but not longbeachae. 

In May, two L. longbeachae isolates had been received at CDC from bronchial wash samples taken from both a 77-year-old Oregon woman and a 45-year-old California man who were both diagnosed with legionellosis. The California patient died and his house was cleaned before an investigation could be undertaken. State and local health officials determined that the Oregon patient had been potting plants using commercial potting soil mixtures and had been working in a home garden during the 10 days before her symptoms began in April. Two potting soil samples taken from her residence were tested for Legionella at CDC; one was positive for L. longbeachae.
Isolates of L. longbeachae from the patients and soils will be compared using amplified fragment length polymorphism typing. 

Reported by: JS Duchin, MD, J Koehler, DVM, Public Health--Seattle & King County, Seattle; JM Kobayashi, MD, State Epidemiologist, Washington State Dept of Health; RM Rakita, MD, K Olson, MD, NB Hampson, MD, Virginia Mason Medical Center, Seattle. DN Gilbert, MD, JM Jackson, Providence Portland Medical Center, Portland; KR Stefonek, MPH, MA Kohn, MD, State Epidemiologist, Oregon Dept of Human Svcs, Health Div. J Rosenberg, MD, D Vugia, MD, Acting State Epidemiologist, California
Dept of Health Svcs. M Marchione-Mastroianni, CDC Foundation, Atlanta, Georgia. Respiratory Diseases Br, Div of Bacterial and Mycotic Diseases, National Center for Infectious Diseases; and EIS officers, CDC. 

Editorial Note:

The findings in this report illustrate the importance of reporting cases of LD to local and state health officials and of culturing patient specimens for Legionella. Although urine antigen tests provide rapid and accurate diagnosis of Legionella pneumophila serogroup 1, these tests are not sensitive for other serogroups or species.
Microbiologic and epidemiologic investigations are needed to identify less common species and may reveal risk factors and novel modes of disease transmission. 

L. pneumophila serogroup 1 accounts for most legionellosis cases in the United States; L. longbeachae is reported less frequently. During 1990--1999, 37 cases of L. longbeachae were reported to CDC's Legionella reporting system. It is likely that legionellosis is underreported to CDC because of failure to obtain the appropriate
diagnostic tests in cases of pneumonia of unknown etiology, difficulty of culturing Legionella from clinical specimens, and because legionellosis is not reportable in all states. 

Soil surveys for Legionella have not been conducted in the United States; however, in a soil survey in Australia, 33 (73%) of 45 potting soil samples tested positive for Legionella; 26 (79%) of the 33 contained longbeachae (4). Nineteen (100%) soil samples in Europe and the United Kingdom were negative for L. longbeachae. 

A survey of 17 soil samples in Japan in 1998 yielded 31 different strains of Legionella; eight of the 17 samples (47%) contained L. longbeachae (3). 

Health-care providers should report legionellosis cases to local or state health departments, and state health departments should report legionellosis cases, particularly L. longbeachae to CDC. Risk factors and behaviors associated with transmission of L. longbeachae are unknown; therefore, to better define the extent of disease,
modes of transmission, and to develop prevention strategies, CDC urges state health departments to send Legionella cultures yielding non-pneumophila isolates to CDC's Legionella laboratory for speciation, telephone (404) 639-3563. Cases of L. longbeachae infection that have occurred during the previous 12 months should be  reported to CDC's National Center for Infectious Diseases, Division of Bacterial and Mycotic Diseases, Respiratory Diseases Branch, telephone (404) 639-2215. For local and state use, a case report form may be obtained from the World-Wide Web, 

and faxed to (404)639-3970. 


1.Fiore AE, Nuorti JP, Levine OS, et al. Epidemic Legionnaires' disease two decades later: old sources, new diagnostic methods. Clin Infect Dis 1998;26:426--33. 

2.Steele TW, Lanser J, Sangster N. Isolation of Legionella longbeachae serogroup 1 from potting mixes. Appl Environ Microbiol 1990;56:49--53. 

3.Koide M, Saito A, Okazaki M, et al. Isolation of Legionella longbeachae serogroup 1 from potting soils in Japan. Clin Infect Dis 1999;29:943--4. 

4.Steele TW, Moore CV, Sangster N. Distribution of Legionella longbeachae serogroup 1 and other Legionella in potting soils in Australia. Appl Environ Microbiol 1990;56:2984--8. 

Source MMWR at

ATLANTA, Sep 01 (Reuters Health) - The acquisition of legionellosis, involving Legionella longbeachae rather than L. pneumophila, from contaminated potting soil has been reported for the first time in the United States.

In May and June of this year, residents of three states (California, Oregon, and Washington) were diagnosed with Legionnaires' disease and in two cases, potting soil handled by the patients tested positive for L. longbeachae. The third patient had also been handling potting soil, but it could not be tested.

"This association between Legionnaire's disease and potting soil had been previously reported in Australia and Japan but this is the first time we have recognized it in the United States," said Dr. Michael Martin, officer with the Epidemic Intelligence Service Officer for the Centers for Disease Control's National Center for Infectious Disease in an interview with Reuters Health.

"[L.] pneumophila serogroup 1 accounts for most legionellosis cases in the United States; L. longbeachae is reported less frequently," according to the authors of the report in the September 1st issue of the CDC's Morbidity and Mortality Weekly Report. "During 1990-1999, 37 cases of [L.] longbeachae were reported to CDC's Legionella reporting system. It is likely that legionellosis is underreported to CDC," they write.

"It can be difficult to diagnose," Dr. Martin explained. "Patients present with flu-like symptoms: fever, headaches, muscle-aches and pain and maybe pneumonia, so it often presents much like any other pneumonia."

"Physicians need to be sure to think about Legionella when they see patients with pneumonia," he said. "Certainly if they do diagnose Legionella, they should report that to their local or State health department."

Dr. Martin added that it would premature to recommend avoiding potting soil. "We don't know quite yet the risk factors and behaviors that might be involved with infection."

Legionella longbeachae pneumonia in a gardener.

A 52-year-old male gardener, who traveled to Guam Island several days ago, was admitted to our hospital with fever, cough and dyspnea. His chest X-ray showed bilaterl infiltration and he was severely hypoxic and hypotensive on admission. He died of multiple organ failure in spite of intensive treatment with mechanical ventilation antibiotics including erythromycin.
Legionella longbeachae serotype 1 was isolated from his sputum and was regarded as the etiologic agent. Legionella longeachae was not isolated from the same type of leaf mold that he used as potting soil.
This is the first case of Legionella longbeachae pneumonia from whom the organism was isolated in Japan.
Kansenshogaku Zasshi 1998 Oct;
Okazaki M, Umeda B, Koide M, Saito A
Respiratory Division, Kobe City General Hospital.

Legionnaires' alert after five cases

28th May 1998

A 75-year-old woman gardener, believed to have contracted legionnaires' disease from potting mix, remained in hospital last night following the discovery last week of five cases of the potentially fatal disease in northern Sydney and the Blue Mountains.

The Minister for Health, Dr Refshauge, said there was no common link between the five cases. The other four people are believed to have contracted the disease from unidentified airconditioning systems.

The woman from northern Sydney, was last night in a satisfactory condition.

The others - two northern Sydney women aged 43 and 59, a 47-year-old north Sydney man and a 58-year-old Blue Mountains man - were released from hospital after responding to antibiotics.

The four northern Sydney people live in different suburbs and had not visited any common sites such as shopping centres.

The suburbs where the disease was contracted have not been named to protect patient confidentiality, but the Northern Sydney Area Health Service covers suburbs such as Hornsby, Mona Vale, Manly, Ryde and Gladesville.

A spokesman for Dr Refshauge said the outbreak of a number of cases in a single week, which accounted for almost half of this year's legionnaires' disease notifications, appeared to be a coincidence.

He said it was generally accepted in the scientific community that a single source of contamination would result in a multiple outbreak.

The disease has an incubation period of more than one week and NSW health officials are monitoring the situation to see if other people develop symptoms that might link them to the five confirmed cases.

Legionella bacteria are found naturally in the environment and are most commonly spread by inhaling contaminated air. Legionella pneumophilia can build up in cooling towers of air-conditioning systems, spa pools or shower heads. Legionella longbeachae occurs in soil and compost.

The bacteria cannot be spread from person to person.
(I question this statement)(DG)

HDWA Press Release

The Health Department has issued a warning to gardeners to take precautionary steps to prevent Legionella infection from potting mix and other compost materials.

The warning comes following the notification of 10 cases of Legionella longbeachae in the past three months.

Legionella longbeachae is commonly found in potting mix, soil, peat, mulch and garden composts.

Legionella infection can cause severe pneumonia in susceptible people. Typical symptoms include fever, headache, muscle pains, difficulty in breathing, cough, diarrhoea, vomiting, and mental confusion.

Males over 50 years of age are most at risk, especially smokers and former smokers, as well as people with diabetes, liver disease or lowered immunity.

About 15 per cent of hospitalised cases result in death.

"The warmer spring weather is ideal for the Legionella bacteria to grow," Environmental Health Director Michael Jackson said.

"People should take the following special precautions in the garden:

open potting mix bags with care to avoid inhaling airborne potting mix;

moisten the contents of the bag on opening - make a small opening and insert a garden hose to dampen the potting mix;

wear gloves to avoid transferring potting mix from hand to mouth;

always wash hands after handling potting mix, even if gloves have been worn;

take the same precautions when handling soil, peat, mulch and garden composts.

"Legionnairesí disease is an illness that can severely debilitate people.

"If people develop the described symptoms, especially fever, headache, difficulty in breathing and mental confusion, they should see their doctor immediately.

"Antibiotic treatment is effective if it is not delayed,"

Media Contact:

Gardeners warned of the danger of Legionnaires' disease

Potting mix and other compost materials coupled with the warm summer sun is a recipe most gardeners follow to promote garden growth, but - the Health Department warns - beware of what else these ingredients may grow.

The warning follows the notifications of nine cases of Legionella longbeachae in the past two months, possibly contracted through contact with potting mix or other compost materials.

Legionella infection can cause severe pneumonia in susceptible people. Typical symptoms include fever, headache, muscle pains, difficulty in breathing, cough, diarrhoea, vomiting and mental confusion. "Legionella long can be found in potting mix, soil, peat, mulch and garden composts," Environmental Health Director Michael Jackson said.

"And the warmer weather is ideal for the Legionella bacteria to grow."

People should take the following precautions in the garden:

open potting mix bags with care to avoid inhaling airborne potting mix; moisten the contents of the bag on opening make a small opening and insert a garden hose to dampen the potting mix; wear gloves to avoid transferring potting mix from hand to mouth; always wash hands after handling potting mix, even if gloves have been worn; and take the same precautions when handling soil, peat, mulch and garden composts.

Males over 50 years of age were most at risk, especially smokers and former smokers, as well as people with diabetes, liver disease or lowered immunity. Nearly 15 per cent of hospitalised cases resulted in death, but antibiotic treatment, if not delayed, was very effective in treating the infection.

Magazine of the WA Health Department
Summer 1997/1998


Legionella longbeachae blamed for four deaths

Health authorities have confirmed there has been an outbreak of legionella disease in Cairns, which it is suspected has killed four people over the past couple of months.
The cause of the outbreak is reported to be from Potting Mix

A spokesperson from the Tropical Public Health Unit in Cairns says two people have definitely died from the disease but says it will be impossible to determine if the other two died from legionella.

The disease is different from legionaires' disease, which is carried through air conditioning systems.

The health unit says legionella longbeachae is spread through potting mixes and soil.

1986 Sweden

A previously healthy 50 year old greenhouse repairman fell ill with pneumonia, this report is the first probable case of Legionella longbeachae infection in Sweden.
(Eitrem R, Scandinavain J of Infectious Diseases, 1987 19 381-382)

Legionella longbeachae pneumonia: report of two cases

Lim, Irene; and others 
 Legionella longbeachae serogroup 1 was isolated from the respiratory secretions of two patients with community- acquired pneumonia. One patient had a mild infection without evidence of the involvement of other organs and recovered, in spite of inappropriate antibiotic therapy. The other patient was severely-ill on presentation with multisystem failure and died soon after admission to hospital. The organisms were identified by the immunofluorescence technique and by quantitative DNA- hybridization studies. The sources of the infection in these patients are unknown as the organism has never been isolated from the South Australian environment. (Source: Lim I et al. Legionella longbeachae pneumonia: report of two cases. Med J Aust 1989; Vol.150 : 566-601.

Following a statewide outbreak of legionellosis due to Legionella longbeachae in South Australia in 1988 and 1989 studies were performed to find the source. Legionella longbeachae was isolated from a number of potting mixes. The isolation of Legionella longbeachae from some potting mixes suggest that soil rather than water is the natural habitat of this species and may be the source of human infection.
(Steele.TW, Appl Environmental Microbiology 1990 56--49-53)

Legionella longbeachae and other Legionella spp, were isolated from 73% of 45 potting soils made in Australia by 13 manufactures, between March 1989 and May 1990.
(Steele TW, Appl Environmental Microbiology 1990 56 (10) 2984-2988)

Eng, R.H.K. et al.,
`Legionnaires' Disease in a Gravedigger',
New York State Journal of Medicine, vol.84, pp. 234-40.

Trouble in the potting shed.
(Anonymous, Lancet, 1990 july 21 151-152 336: 8708)

Western Australia recorded its first outbreak of Legionnaires' Disease in July 1996 in the town of Esperance which is in the South West of that state.
The main source of sporidic cases (76%) of Legionnaires Disease in Western Australia is Legionella Longbeachae which normally is associated with potting mix

Panic in the potting shed, Is gardening a health hazard. Legionela longbeachae has been found in Australian potting mix
(Ruchlemann, Medical J Australia 1996--164--36-38)

Recurrent Legionella longbeachae pnumonia associated with re-exposure to potting soil
(DeWit D Guy D, Fopster K Aust N Z Journal Medicine 26(6) 856-857 Dec 1996)

Legionella longbeachae in Western Australia
(Ross IS, Mee BJ, Riley TV. Medical Journal Australia 166(7) 1997)

Fatal case of Legionnaires' disease from gardening

A79 year old women was found to be suffering from Legionellosis and died 36 hours later,
it was an intersting fact that the women suggested her diagnosis because of recent cases in the media. it was found that Legionella longbeachae was the main cause of death
(Kingston M New Zealand Medical Journal p111 23 March 1994)


An apparent increase in notified cases of Legionella infection in Western Australia occurred in late 1994. Although an examinalion of data from previous years supported the likelihood that this was a seasonal effect, a review of all reported cases for 1994 was conducted in order to identify any clustering of cases or common risk factors.


'Twenty-six notifialions were identified from the Health Department of Westrrn Australia infectious diseases dadatabase for 1994, Further information was compiled from Legionella data sheets which were completed by both Communicable Disease Control unit medical staff and HDWA Envirnnmental Health Officers, and were available for 24 of the cases.

Case definition
Notified patients had to fulfill at least one of thc following criteria to be accepted as a case:
(1) isolation of Legionella from the patient
(2) a fourfold rise in antibody titre between acute and convalescent phase sera
(3) seroconversion to a titre of at least 256 and a compatible clinical illness
(4) a single titre of at least 512 and a compatatible clinical illness


Nineteen cases (79%) werc male and five (2I %) were female. The ages ranged from 25 to 8I years (mean 59 years). Twenty-two cases resided in the Perth metropolitan area and one case came from each of the Kimberley, Central and Great Southern regions. There was no evidence of clustering by postcode. Eight cases (33%) were employed, 13 cascs (54%) were retired, one case was an invalid pensioner, one was unemployed and the employment status of one case was unknown.
Seventeen patients (71%) presented between August and December, and the peak occurred In October when seven cases werc notified (Figure).
Twenty patients presented with clinical features of acute lower respiratory tract lnfection and another had fever with chest X-ray evidence of pneumonia. Information on the presenting clinical syndrome of three patients was missing.
Twenty patients were hospitalised. Data were incomplete for four of these patients, however, for the other 16 the lenght of hospital stay was between 6 and 39 days (median 14.5 days, mean 16.9 days).
Three cases were admitted to intenisivc care units. Two required ventilation, one case because of a collapsed lung, and another case for respiratory failure.
All three cases suvived.
There was two deaths giving case fatality of 8.3%. Case 4 died 19 days after admission for pneumonia . A single scrum specimen taken on day 11 showed a titre of 5I2 to L.Longbeachae. According to his wife he spent every spare moment in the garden.
L. Longbeachae was subsequently isolated from
PEAT MIX at his home.
Case 11 also died from pneumonia. He had an increase in titre to L. longbeachae from 512 fo 32,768 over an 11 day period.

Laboratory diagnosis

Thc serolgical test used was the indirect fluorescent antibody test, conducted at the State Health Laboratory Services.
Nineteen patients had a fourfold or greater rise in litre with paircd sera and five others had a single titre of >512 and an illness compatatible with Legionella pneumonia.
Eighteen cases had serological evidence of L longbeachae alone.
Four cases had serological evidence of L.pneumophila alone and two cases had increased titre to both species.
In only two cases was Legionella isolated. Both isolates were L.pneumophila serogroup 1, one was cultured from bronchoalveolar respiratory secretions.

Potential risk factors

Most patients had gardening exposure or one or more potential predisposing factors for Legionellosis.
Casc 17 worked in an environment with opportunities for exposure to Legionella.
He was a rural watcr authority worker who cleaned the inside of a waste water treatment tank with a high pressure hose 18 days before the onset of symptoms. Over seven days, he seroconverted to L.pneumophila serogroups 1 and 2 (titres were respeclively 256 and 512), and additionally had a titre of 128 to L.pneumophila serogroup 4.
Thirteen cases (all with L.longbeachae infection) were keen gardeners and seven of them gave a precise history iof gardening activities wliich involved the handling of potting soil or mulch between six and ten days prior to their first symptoms. Samples of peat, soil or potting mix were collected from six of the gardener cases: in four instances no Legionella were grown; one sample which was collected five weeks after the patient's L. longbeachae infection grew L.bozenianni, L. longbeachae was cultured from peat mix and a Legionella species was isolated from soil conditioner at the home of case four.

Samples wcre takcn from home water fixtures of six cases (two with L. pneumophila and four with L. longbeachae) but no Legionella were isolated from these sources.
Four of thc cases had no potential predisposing factors for Legionellosis and fivc cases had agc 65 years or over only. Of this group, six were regular gardeners of whom four had just uscd mulch or potting soil just before the illness onset. Two L.longbeachae cases, however, had no known risk factors.
Three cases were diagnosed with Legionella infection during hospital admissions for
unreated conditions. Cases 23 and 21 developed symptoms four and seven days respectively after admission for elective surgery.

Althoug consistent with possible nocomal infection, both cases were active gardeners with L. longbeachae infection, therefore it is morc likely that their infections were community acquired. Case nine was an inpatient at a large teaching hospital for 47 days before the onsct of Legionellosis caused by L. pneumophila. She had occasional home leave during this time but was housebound by her illness. Testing of her home water fixtures did not reveal a source of Legionella.

Notified cases of Legionellosis in
Western Australia, 1994 by month of onset

AVERAGE FOR 1991 TO 1994

(Rosie Brennan,Communicable Disease Control Unit , Health Dept Western Australia
(CDI 16 October Vol19/21 1995)


Potting mix

"A 71 year old Sydney man, who is believed to have caught the disease after using potting mix late last year. is still in hospital. -When using potting mix, people should try not to breathe In the dust when they open the bag, and should moisten the mix before working with it to minimise the dust. "Thorough hand washing and wearing a dust mask are other ways to avoid the disease. 'People over 60 years are more likely to become infected, and should take special care. "There are warnings about Legionnaires on potting mix bags.


Western Australian doctors are treating more than two cases a month of Legionnaire's disease - and garden potting mix is being blamed as a major cause, calls for mandatory warning labels on all soil products which could carry the bacteria. Of 164 reported cases of the disease since 1988, a large number were related to soil and potting mix.
Sir James Cruthers, 72. The Sunday Times Chairman is still recovering from the disease.
Sir James was using commercial potting mix in his Mosman Park home.
He was rushed to hospital in a serious condition and remained in intensive care for three days.
One woman is believed to have settled out of court with a manufacturer - but according to an industzy spokesman, other cases are occurring around Australia.

It was stated that the chief executive of the Nursery Industry Association of Australia, would welcome mandatory signs on potting mix bags. He blamed the "cowboy" attitude ot some manufacturers for refusing to self regulate.
Since 1988, 19 West Australians have died from Legionnaires' disease - about two deaths a year. Last year, 30 cases were reported.
(Source Media)


A PERTH man left blind after a battle with Legionnaires' disease says he caught the deadly bug from home-made compost. he warns that even humble grass clippings and garden waste could become a fertile breeding ground for the bacteria.He says that the the clippings had been given away by a bowling club to members who wanted it for composting.
It was also stated that another man who had some of the compost, which had been stored in a bin for some time, also contracted a milder form of the disease and sought medical advlce sooner.
When his family sought medical help, he was put into intensive care and was on life surport system in Hospital for several weeks.
His wife said that his heart gave out as well as his Kidneys and Liver.
The disease is being blamed for a serious deterioration in the mans eyesight
(Source Media)

This is the first case that i have come across which involves home made compost,
This should be a warning to all keen gardeners to be very carefull when handling any form of COMPOST, potting mix or soil conditioner.
(Denis Green)

All cases were sporadically distributed throughout the year
In 1992 there was 21 cases

Western Australia, January 1998

This article shows the dangers of SOIL

The rare bacterial infection, melioidosis, has claimed three lives in the first recorded outbreak of the disease in Western Australia. The One Arm Point community in the Kimberley is mourning a 57-year-old man and two women aged 51 and 41 who died after they were infected. Melioidosis is caused by a ubiquitous soil bacterium - _Pseudomonas pseudomallei_ [_Burkholderia pseudomallei_]- and contracted either by walking through contaminated soil or ingesting contaminated water. Infection is relatively common in the rice paddies of South East Asia but the last Austra1ian outbreak was in the summer of 1990-91, when 14 people died in Darwin, Townsville and Cairns. There have been only 90 cases in the previous 30 years. The One Arm Point deaths are the first known fatalities from melioidosis in Western Austraila and is the first recorded cluster of cases in the State.

It has affected five people since November, including the three who died between late November and New Year's Eve. A 51-year-old woman is being treated in hospital and another 52-year-old man is receiving antibiotics as an outpatient. There was one other case of infection, in a 45-year-old man, recorded and treated in the community in February last year. WA Health Department director of disease control Jag Gill said the disease was extremely rare in Australia and usually proved fatal only in people with existing serious medical conditions. All of these three people had some condition that made them susceptible to the illness and to death," Dr Gill said. Chronic lung disease, renal failure or diabetes made people vulnerable and most health people were able to fight off melioidosis without showing any symptoms. Acute infection resulted in pneumonia or septicaemia, with symptoms of fever, aches, pains and abdominal cramps.

Floods, heavy rain and hot weather are associated with outbreaks of the disease but Dr Gill said it was suspected that earthworks at One Arm point in October had stirred up the bacteria. Tests on the water supply had come back free of the organism but soil samples would not be fully analysed until the end of the week. Transmission was mostly made possible through contact of the soil with broken skin. Wearing shoes and cleaning and covering all cuts was the best method of prevention.

Infection in other remote Kimberley communities was improbable and Dr Gill said no specific warnings had been issued. "lt's not worth testing (other One Arm Point residents) because many people infected have immunity and are a symptomatic," Dr Gill said. There was no chance of the bacteria becoming a threat in the metropolitan area the disease, which occurs in soil and water throughout the world, was the biggest bacterial killer in the Northern Territory and north-east Thailand during the tropical wet season. Australia's most widely published expert on melioidosis, Associate Professor Bart Currie, of Royal Darwin Hospital, said such a cluster in the East Kimberley before the wet season in November and December was unprecedented. Almost certainly it`s related to the earthworks Professor Currie said.

This disease is the most prevalent cause of community acquired pneumonia, liver abscess, splenic abscess and sepsis in parts of Thailand. In Bangkok teaching hospitals it is always considered in the differential diagnosis of any obscure febrile illness. The organism is easy to culture and can be suspected on a Gram stain (bipolar staining Gram negative bacillus). A high level of awareness should allow early diagnosis and appropriate treatment (high dose IV ceftazidime with cotrimoxazole, doxycycline or amoxiclav - 2 drugs). Long term oral therapy (2-6 month) should follow when patient is improved and afebrile as relapses are common and often delayed. We recently had seen several expatriates, one a tunneling engineer who got pulmonary melioidosis - acute form within the city , probably on his job site. Mortality should be low if diagnosis is suspected and aggressive therapy instituted unless it is the overwhelming septicemic form. Disease in Thailand is most common in farmers, diabetics and people with renal disease. The 3 expatriates seen recently all were normal hosts.

Good references are: Woods ML Clin Inf Dis 1992; 15: 163-169. Chaowagul W. J Infect Dis 1993; 168: 1181-85. Dhiensiri T. Radiology 1988; 166: 711-715. Kosuwan W.J. Bone Joint Surg. 1993;75:1811-1815.

The following background information on melioidosis in Australia and several surrounding countries were abstracted from the GIDEON software program:


- Melioidosis was first described in north Queensland sheep in 1949, with the first human case reported in 1950.

- This is the most common cause of fatal bacteremic pneumonia in the upper Northern Territory.

- The disease is most common in Far North Queensland and the Northern Territory. Sporadic cases are also reported from Western Australia and Torres Strait Islands.

- 33 cases (36% fatal) were reported from Northern Territory during November 1990 to June 1991 (25 of these from Darwin); 28 (6 fatal) during the wet season of 1993 to 1994; 21 (3 fatal) during the wet seasons of 1994 to 1995. Two fatal cases were reported from Southeast Queensland in 1996.